The increasing complexity of communication, data, plumbing, gaseous, and electrical systems in use today necessitates the organization and clear labeling of such systems. Examples include communication systems with cables and conduits, laboratory tubing, fire suppression systems supplying a multitude of zones, irrigation systems, swimming pool circulation systems especially those which self-control their chlorine and pH levels, and zoned hot water heating systems in residential and commercial buildings. Labeling of piping used to transfer hazardous liquids and gases is common in industrial buildings and research facilities.
Identification of flexible cords, grounded and ungrounded conductors, etc is required by the National Electric Code (NEC 110-21, 210-4(d), 215.8, 310-11, 333-22, 338-5, 340-6, 348-15(d), 363-17, 402-9, 504-80(b), 725-71(h), 727-5, 800-50, and 820-50), as well as by state and local laws. Complex wiring systems used in hospitals and health care facilities have specific identification requirements under the National Electric Code. In addition, NFPA and ANSI standards require marking of certain electrical wiring and plumbing such as pressure and vacuum piping, and piping used to transfer hazardous substances (NFPA 3-9, 2-7.7, 7.6.6, 7.7.6, 2-4.4, 2-4.3, and 4-6). Identification of valves used in fire suppression systems is required by NFPA as well (NFPA 4-2.8.1 through 4-2.8.3).
Labeling of piping and wiring which is not required by national standards makes maintenance work easier, facilitates usage of specialized piping, and saves time in tracing the source or destination of wiring and piping. Information can also include who to call for service, maximum rated pressures, gas line identification, the purpose of a valve, how a valve relates to another valve, direction and rate of flow, emergency shut-off instructions, etc. Levels of safety are increased by providing cautionary markers on hazardous piping or directly on valves, for example, extreme temperatures. Such marking is extremely useful in emergencies since reading information prominently displayed on the pipe or valve of concern and immediately acting on the information closely parallels human thought processes that occur in an unexpected situation. This is of obvious interest to insurance companies.
Labeling of cables and pipes in the past has included handwriting on the pipe surface, which is problematic in many ways. Writing on a round or curved surface is difficult, especially if the outside diameter is small, frequently producing a sloppy or illegible result. The total surface area available for labeling is limited and often not conveniently placed for easy reading. Repairs or replacement of the underlying pipe or conduit destroys any written information thereon. Painted markings, tied-on handling paper, plastic tags, or colored tape bands are subject to peeling and corrosion, easy removal, and require referring to a legend or master coding sheet.
Other pipe identification systems include wrapping straps attached to an information plate around piping, such as the pipe identification system disclosed in U.S. Pat. No. 4,246,712. This method is subject to many limitations. For example, the method does not allow for the labeling of surface mounted piping or conduit, as there is no space to wrap the straps. It does not allow for an adjustable multi-position labeling surface. It is not usable in installations where pliers are necessary to tighten adequately the straps. It is subject to loosening and rotation from mechanical, vehicular or natural vibration. It is also subject to lateral slippage along a vertical pipe or a horizontal pipe from such vibration, thus becoming improperly located with possible disastrous results. Also, this method makes it more difficult to change a label if so desired.